River ice kinematic data measurements during winter frazil ice flow and spring ice breakup are necessary for: i) analysis of river/ice dynamics and ii) flood hazard or water resource assessment. Present methods for obtaining this data are hazardous, difficult and time consuming. Additionally, some of these current methods can provide early warning to potentially flood prone communities down river due to resulting flooding caused by river/icing conditions during a spring thaw. Having such an early warning system minimizes loss of life and property damage by giving affected communities enough time to take appropriate measures.
There are two known methods for detection of ice sheet movement. The first method entails full time observation by a person which has an obvious limitation of not being reliable due to darkness and/or low-visibility weather conditions. The second method entails instrumentation specifically designed to detect river ice motion without the need of human intervention. This instrumentation comprises a wire embedded in a river ice sheet which provides a one-time indication of ice movement. When the ice moves, the wire breaks, opening a circuit which trips an alarm. Limitations of this method includes: i) an initial potentially hazardous wire deployment across an ice sheet or rubble field, and ii ) physically positioning such a system along a river bank where ice scour of the river bed and banks often can occur thus preventing use of this method. Such instrumentation is disclosed in U.S. Pat. No. 4,680,961 entitled "System and Method For Ice Movement Detection In Determination of Ice Breakup."
Moreover, both of these methods above are not adequate for determining kinematic data of the ice, i.e. velocity or acceleration thereof. Such data is important for: i) analyzing river/ice dynamics and ii) determining the magnitude of potential flooding of towns down river of the ice cover. Current kinematic data methods for determining ice sheet and rubble ice conditions during ice breakup use video data recording techniques which require tedious, frame-by-frame motion analysis of the video data of such an event. Limitations of such a method include: i) equipment and operator must be present at the event; ii) this technique is ineffective during night or poor visibility conditions; and iii) requires the inclusion of known reference landmarks in a video frame for accurate kinematic measurements of the ice which may not be practical under certain viewing conditions.
Since no methods or hardware exist for either detecting river ice motions or determining river ice kinematic measurements that: i) requires no observer intervention, ii) is unaffected by darkness and/or low visibility conditions, or iii) is resetable for multiple events; the microwave Doppler radar system of the instant invention herein solves these problems.